#' Dotabuff theme for highcharts
#' 
#' @param ... A named parameters to modify the theme.
#' 
#' @examples
#'
#' highcharts_demo() %>%
#'   hc_add_theme(hc_theme_db())
#' @export
hc_theme_db <- function(...) {
  theme <-
    list(
      colors = c("#A9CF54", "#C23C2A", "#FFFFFF", "#979797", "#FBB829"),
      chart = list(
        backgroundColor = "#242F39",
        style = list(
          color = "white"
        )
      ),
      legend = list(
        enabled = TRUE,
        align = "right",
        verticalAlign = "bottom",
        itemStyle = list(
          color = "#C0C0C0"
        ),
        itemHoverStyle = list(
          color = "#C0C0C0"
        ),
        itemHiddenStyle = list(
          color = "#444444"
        )
      ),
      title = list(
        text = NULL,
        style = list(
          color = "#FFFFFF"
        )
      ),
      tooltip = list(
        backgroundColor = "#1C242D",
        borderColor = "#1C242D",
        borderWidth = 1,
        borderRadius = 0,
        style = list(
          color = "#FFFFFF"
        )
      ),
      subtitle = list(
        style = list(
          color = "#666666"
        )
      ),
      xAxis = list(
        gridLineColor = "#2E3740",
        gridLineWidth = 1,
        labels = list(
          style = list(
            color = "#525252"
          )
        ),
        lineColor = "#2E3740",
        tickColor = "#2E3740",
        title = list(
          style = list(
            color = "#FFFFFF"
          ),
          text = NULL
        )
      ),
      yAxis = list(
        gridLineColor = "#2E3740",
        gridLineWidth = 1,
        labels = list(
          style = list(
            color = "#525252"
          ),
          lineColor = "#2E3740",
          tickColor = "#2E3740",
          title = list(
            style = list(
              color = "#FFFFFF"
            ),
            text = NULL
          )
        )
      )
    )

  theme <- structure(theme, class = "hc_theme")

  if (length(list(...)) > 0) {
    theme <- hc_theme_merge(
      theme,
      hc_theme(...)
    )
  }

  theme
}
